1. Field of the Invention
The present invention relates to an antenna device that has a coil element, and an electronic apparatus provided with such an antenna device.
2. Description of the Related Art
An antenna device that uses a metal member, such as a metal housing of an electronic apparatus, as a radiation element is disclosed in, for example, International Publication No. 2014/003163. This antenna device is configured so that a feed coil connected to a feed circuit may be coupled with a loop mainly by a metal member of an electronic apparatus, and the loop defines and functions as a radiator of magnetic flux.
While, in the antenna device that uses a metal member, such as a metal housing of an electronic apparatus, as a radiation element, in order to improve the function of a loop as a radiator of magnetic flux, an opening of the loop may be enlarged, the restriction of space is strict. In other words, it is difficult to provide an antenna device that achieves both space-saving and a high gain.